remove dead code

Author: gares

src/dune_rules/coq/coq_config.ml

@@ -219,14 +219,6 @@ let impl_config bin =
 
 let config_memo = Memo.create "coq-config" ~input:(module Path) impl_config
 
-let _version ~coqc =
-  let open Memo.O in
-  let+ t = Version.make ~coqc in
-  let open Result.O in
-  let+ t = t in
-  t.version_string
-;;
-
 let make ~(coqc : Action.Prog.t) =
   let open Memo.O in
   let+ config_output =